You can find all the errors in the error.log file.
Thanks for that. :) I noticed that the error.log filed is stored in 'Applications' which is very unusual for an osx app. Generally they are stored in ~/Documents/<Game Name>. Anyway here is a copy/paste of my error.log.. The earlier errors are when I first got an error after loading and the latter I think is occurring now that I can't load the save.
Timestamp : 21-5-13 11:11:02
Error level : ERROR
Message : Lua hook OnEnter caught ELuaStateException!
Call path : levels[town].OnEnter
Call params : (true)
Error message : Lua error : lua/levels//town.lua:189: Position expected!
Timestamp : 21-5-13 11:23:49
Error level : ERROR
Message : Lua hook OnEnter caught ELuaStateException!
Call path : levels[town].OnEnter
Call params : (false)
Error message : Lua error : lua/levels//town.lua:189: Position expected!
Timestamp : 21-5-13 11:28:18
Error level : FATAL EXCEPTION
Message : Fatal exception encountered
An unhandled exception occurred at $0000000100040E4B :
EInvalidCast : Invalid type cast
$0000000100040E4B
Timestamp : 21-5-13 11:28:28
Error level : FATAL EXCEPTION
Message : Fatal exception encountered
An unhandled exception occurred at $0000000100041BD9 :
EAccessViolation : Access violation
$0000000100041BD9